Radar metrology system including calibration

Abstract

A radar metrology system is provided for use with a movement system (e.g., a robot arm) that moves an end tool, and includes mobile and stationary radar configurations. The mobile radar configuration includes mobile radar components that are coupled to the end tool or an end tool mounting configuration. The stationary radar configuration includes stationary radar components (e.g., that surround a volume in which the end tool is moved). As part of a calibration process, the mobile radar configuration is moved to a plurality of calibration positions, and received radar signals are utilized to determine distances between stationary radar components and one or more mobile radar components. The radar signals are either transmitted from stationary radar components and received by mobile radar components, or vice versa. The locations (e.g., coordinates) of the stationary radar components are determined based at least in part on the determined distances.

1 . A radar metrology system for use with a movement system that moves an end tool,
 the movement system comprising:
 a movable mechanical configuration comprising an end tool mounting configuration that an end tool is configured to mount to; and 
 a motion control system configured to control an end tool position and orientation, based at least in part on controlling the movable mechanical configuration so as to move at least a portion of an end tool that is mounted to the end tool mounting configuration within a movement volume, 
   the radar metrology system comprising:
 a mobile radar configuration comprising a plurality of mobile radar components that are configured to be coupled to at least one of the end tool or the end tool mounting configuration; 
 a stationary radar configuration comprising a plurality of stationary radar components that define at least part of a metrology frame volume that surrounds at least part of the movement volume in which at least a portion of the end tool is moved; 
 a processing portion configured to perform a calibration process comprising:
 controlling the movement system to move the mobile radar configuration to a plurality of calibration positions; 
 for each calibration position, utilizing received radar signals to determine distances between stationary radar components of the stationary radar configuration and one or more mobile radar components of the mobile radar configuration, wherein the radar signals are at least one of transmitted from the stationary radar components and received by the one or more mobile radar components, or transmitted from the one or more mobile radar components and received by the stationary radar components; and 
 determining locations of the stationary radar components of the stationary radar configuration based at least in part on the determined distances. 
 
   
     
     
         2 . The radar metrology system of  claim 1 , wherein the processing portion is further configured to perform a first measurement process after the calibration process has been performed and the end tool has been moved by the movement system to a first measurement position, the first measurement process comprising:
 utilizing received radar signals to determine distances between stationary radar components of the stationary radar configuration and mobile radar components of the mobile radar configuration, wherein the radar signals are at least one of transmitted from the stationary radar components and received by the mobile radar components, or transmitted from the mobile radar components and received by the stationary radar components; and   determining a first measurement position and a first orientation of the end tool based at least in part on the determined distances between stationary radar components and mobile radar components and based at least in part on the determined locations of the stationary radar components.   
     
     
         3 . The radar metrology system of  claim 2 , wherein the processing portion is further configured to perform a second measurement process after the calibration process and the first measurement process have been performed and the end tool has been moved by the movement system to a second measurement position that is different than the first measurement position, the second measurement process comprising:
 utilizing received radar signals to determine distances between stationary radar components of the stationary radar configuration and mobile radar components of the mobile radar configuration, wherein the radar signals are at least one of transmitted from the stationary radar components and received by the mobile radar components, or transmitted from the mobile radar components and received by the stationary radar components; and   determining a second measurement position and a second orientation of the end tool based at least in part on the determined distances between stationary radar components and mobile radar components and based at least in part on the determined locations of the stationary radar components.   
     
     
         4 . The radar metrology system of  claim 2 , wherein the determining of the first measurement position of the end tool comprises determining coordinates of the end tool within a first coordinate system, and the determining of the locations of the stationary radar components comprises determining coordinates of the stationary radar components within the first coordinate system. 
     
     
         5 . The radar metrology system of  claim 1 , wherein each radar transmitter transmits a radar signal at a different frequency, and the transmitted radar signals comprise a first radar signal transmitted by a first radar transmitter at a first frequency, and a second radar signal transmitted by a second radar transmitter at a second frequency that is different than the first frequency. 
     
     
         6 . The radar metrology system of  claim 5 , wherein the plurality of calibration positions comprises a first calibration position, and the determining of the distances for the first calibration position comprises:
 determining a first distance between a first stationary radar component and a first mobile radar component which are either the first radar transmitter and a first radar receiver, or a first radar receiver and the first radar transmitter, respectively, wherein the first distance is determined based at least in part on the first radar signal which is transmitted by the first radar transmitter at the first frequency and received by the first radar receiver; and   determining a second distance between a second stationary radar component and a second mobile radar component which are either the second radar transmitter and a second radar receiver, or a second radar receiver and the second radar transmitter, respectively, wherein the second distance is determined based at least in part on the second radar signal which is transmitted by the second radar transmitter at the second frequency and received by the second radar receiver.   
     
     
         7 . The radar metrology system of  claim 6 , wherein the determining of the distances for the first calibration position further comprises:
 determining a third distance based at least in part on the first radar signal which is transmitted by the first radar transmitter at the first frequency and received by the second radar receiver.   
     
     
         8 . The radar metrology system of  claim 1 , wherein the determining of the locations of the stationary radar components of the stationary radar configuration comprises utilization of a least squares method. 
     
     
         9 . The radar metrology system of  claim 8 , wherein the number of determined distances correspond to an overdetermined system and the least squares method comprises determining a least squares solution for the overdetermined system. 
     
     
         10 . The radar metrology system of  claim 1 , wherein the plurality of stationary radar components comprises at least three stationary radar components. 
     
     
         11 . The radar metrology system of  claim 1 , wherein the plurality of stationary radar components comprises at least eight stationary radar components. 
     
     
         12 . The radar metrology system of  claim 1 , wherein the plurality of mobile radar components comprises at least four mobile radar components. 
     
     
         13 . The radar metrology system of  claim 1 , wherein:
 when the mobile radar configuration is in a first calibration position and a first orientation, the radar signals that are received correspond to a first set of distances between the mobile radar components and stationary radar components and which indicate that the mobile radar configuration is in the first calibration position and the first orientation; and   when the mobile radar configuration is in a second calibration position and a second orientation that are different than the first calibration position and the first orientation, the radar signals that are received correspond to a second set of distances between the mobile radar components and stationary radar components and which indicate that the mobile radar configuration is in the second calibration position and the second orientation.   
     
     
         14 . The radar metrology system of  claim 1 , wherein the one or more mobile radar components comprises at least a first mobile radar component and a second mobile radar component, and each of the mobile radar components is in a fixed relationship within the mobile radar configuration with a fixed separation dimension between the first and second mobile radar components within the mobile radar configuration, and for which the determining of the locations of the stationary radar components of the stationary radar configuration is further based at least in part on the fixed separation dimension. 
     
     
         15 . The radar metrology system of  claim 1 , wherein for two or more of the calibration positions of the plurality of calibration positions, the orientation of the mobile radar configuration is the same. 
     
     
         16 . The radar metrology system of  claim 1 , wherein the determining of the distances is further based at least in part on:
 determining a phase of each received radar signal; and   determining a number of wavelengths of each received radar signal as occurring between the corresponding radar transmitter and the corresponding radar receiver.   
     
     
         17 . The radar metrology system of  claim 16 , wherein the motion control system is configured to sense a position of the end tool based at least in part on using a plurality of position sensors included in the movable mechanical configuration, and the determining of the number of wavelengths of each received radar signal is based at least in part on the position as sensed by the motion control system. 
     
     
         18 . A method for operating a radar metrology system for use with a movement system that moves an end tool,
 the radar metrology system comprising:
 a mobile radar configuration comprising a plurality of mobile radar components that are configured to be coupled to at least one of an end tool or an end tool mounting configuration of a movement system that moves the end tool; 
 a stationary radar configuration comprising a plurality of stationary radar components that define at least part of a metrology frame volume that surrounds at least part of the movement volume in which at least a portion of the end tool is moved; 
   the method comprising:
 performing a calibration process comprising:
 controlling the movement system to move the mobile radar configuration to a plurality of calibration positions; 
 for each calibration position, utilizing received radar signals to determine distances between stationary radar components of the stationary radar configuration and one or more mobile radar components of the mobile radar configuration, wherein the radar signals are at least one of transmitted from the stationary radar components and received by the one or more mobile radar components, or transmitted from the one or more mobile radar components and received by the stationary radar components; and 
 determining locations of the stationary radar components of the stationary radar configuration based at least in part on the determined distances. 
 
   
     
     
         19 . The method of  claim 18 , further comprising performing a first measurement process after the calibration process has been performed and the end tool has been moved by the movement system to a first measurement position, the first measurement process comprising:
 utilizing received radar signals to determine distances between stationary radar components of the stationary radar configuration and mobile radar components of the mobile radar configuration, wherein the radar signals are at least one of transmitted from the stationary radar components and received by the mobile radar components, or transmitted from the mobile radar components and received by the stationary radar components; and   determining a first measurement position and a first orientation of the end tool based at least in part on the determined distances between stationary radar components and mobile radar components and based at least in part on the determined locations of the stationary radar components.   
     
     
         20 . The method of  claim 19 , further comprising performing a second measurement process after the calibration process and the first measurement process have been performed and the end tool has been moved by the movement system to a second measurement position that is different than the first measurement position, the second measurement process comprising:
 utilizing received radar signals to determine distances between stationary radar components of the stationary radar configuration and mobile radar components of the mobile radar configuration, wherein the radar signals are at least one of transmitted from the stationary radar components and received by the mobile radar components, or transmitted from the mobile radar components and received by the stationary radar components; and   determining a second measurement position and a second orientation of the end tool based at least in part on the determined distances between stationary radar components and mobile radar components and based at least in part on the determined locations of the stationary radar components.   
     
     
         21 . The method of  claim 18 , further comprising controlling each radar transmitter to transmit a radar signal at a different frequency, wherein the transmitted radar signals comprise a first radar signal transmitted by a first radar transmitter at a first frequency, and a second radar signal transmitted by a second radar transmitter at a second frequency that is different than the first frequency. 
     
     
         22 . A radar metrology system, comprising:
 a mobile radar configuration comprising a plurality of mobile radar components that are configured to be coupled to at least one of an end tool or an end tool mounting configuration of a movement system that moves the end tool;   a stationary radar configuration comprising a plurality of stationary radar components that define at least part of a metrology frame volume that surrounds at least part of the movement volume in which at least a portion of the end tool is moved;   wherein the radar metrology system is configured to perform a calibration process comprising:
 controlling the movement system to move the mobile radar configuration to a plurality of calibration positions; 
 for each calibration position, utilizing received radar signals to determine distances between stationary radar components of the stationary radar configuration and one or more mobile radar components of the mobile radar configuration, wherein the radar signals are at least one of transmitted from the stationary radar components and received by the one or more mobile radar components, or transmitted from the one or more mobile radar components and received by the stationary radar components, and each transmitted radar signal is transmitted at a different frequency; and 
 determining locations of the stationary radar components of the stationary radar configuration based at least in part on the determined distances.